论文部分内容阅读
以某特长公路隧道为研究背景,采用缩尺寸试验测试、数值模拟的方法分别对纵向排烟和集中排烟模式下隧道内火灾烟气的蔓延特性进行了研究,并对比分析了两种排烟系统在火灾工况下对烟气的控制效果。结果表明,纵向排烟模式将火灾烟气控制在火源下游并从隧道出口排出,高温烟气蔓延范围较长;集中排烟模式通过排烟阀将烟气抽离行车道,有效地控制了烟气蔓延和沉降,高温烟气维持在行车道的上部空间,主要通过竖井排出隧道。采用纵向排烟模式的坡度隧道烟气控制受烟囱效应影响较大,而在设置排烟道的坡度隧道中,将排烟阀开启进行自然排烟就能有效地减弱烟囱效应。因此,采用集中排烟模式的防灾安全性能要优于采用纵向排烟模式。
Taking a special long-distance highway tunnel as a research background, this paper studied the spread characteristics of fire smoke in the tunnel with vertical exhaust and centralized exhaust by the method of reduced size test and numerical simulation respectively, and compared two types of smoke exhaust System in the fire conditions on the flue gas control effect. The results show that the vertical exhaust mode controls the fire flue gas downstream of the fire source and discharges from the tunnel exit, and the extended range of high temperature flue gas is longer. The centralized exhaust mode pulls the flue gas away from the traffic lane through the exhaust valve to effectively control Smoke spread and settlement, high temperature flue gas maintained in the upper space of the driveway, mainly through the shaft discharge tunnel. The gradient tunnel flue gas control with vertical exhaust mode is greatly affected by the chimney effect. In the gradient tunnel with exhaust flue, the smoke exhaust valve can be opened for natural smoke exhaust can effectively reduce the chimney effect. Therefore, the disaster prevention and safety performance using the centralized exhaust mode is better than the vertical exhaust mode.